Controllability for a Wave Equation with Moving Boundary

We investigate the controllability for a one-dimensional wave equation in domains with moving boundary. This model characterizes small vibrations of a stretched elastic string when one of the two endpoints varies. When the speed of the moving endpoint is less than 1-1/e, by Hilbert uniqueness method, sidewise energy estimates method, and multiplier method, we get partial Dirichlet boundary controllability. Moreover, we will give a sharper estimate on controllability time that only depends on the speed of the moving endpoint

Controllability for a Wave Equation with Moving Boundary

We investigate the controllability for a one-dimensional wave equation in domains with moving boundary. This model characterizes small vibrations of a stretched elastic string when one of the two endpoints varies. When the speed of the moving endpoint is less than 1 − 1/√ , by Hilbert uniqueness method, sidewise energy estimates method, and multiplier method, we get partial Dirichlet boundary controllability. Moreover, we will give a sharper estimate on controllability time that only depends on the speed of the moving endpoint

Interaction Between Leucine and Phosphodiesterase 5 Inhibition in Modulating Insulin Sensitivity and Lipid Metabolism

Purpose: Leucine activates SIRT1/AMP-activated protein kinase (AMPK) signaling and markedly potentiates the effects of other sirtuin and AMPK activators on insulin signaling and lipid metabolism. Phosphodiesterase 5 inhibition increases nitric oxide–cGMP signaling, which in turn exhibits a positive feedback loop with both SIRT1 and AMPK, thus amplifying peroxisome proliferator-activated receptor γ co-activator α (PGC1α)-mediated effects. Methods: We evaluated potential synergy between leucine and PDE5i on insulin sensitivity and lipid metabolism in vitro and in diet-induced obese (DIO) mice. Results: Leucine (0.5 mM) exhibited significant synergy with subtherapeutic doses (0.1–10 nM) of PDE5-inhibitors (sildenafil and icariin) on fat oxidation, nitric oxide production, and mitochondrial biogenesis in hepatocytes, adipocytes, and myotubes. Effects on insulin sensitivity, glycemic control, and lipid metabolism were then assessed in DIO-mice. DIO-mice exhibited fasting and postprandial hyperglycemia, insulin resistance, and hepatic steatosis, which were not affected by the addition of leucine (24 g/kg diet). However, the combination of leucine and a subtherapeutic dose of icariin (25 mg/kg diet) for 6 weeks reduced fasting glucose (38%, P,0.002), insulin (37%, P,0.05), area under the glucose tolerance curve (20%, P,0.01), and fully restored glucose response to exogenous insulin challenge. The combination also inhibited hepatic lipogenesis, stimulated hepatic and muscle fatty acid oxidation, suppressed hepatic inflammation, and reversed high-fat diet-induced steatosis. Conclusion: These robust improvements in insulin sensitivity, glycemic control, and lipid metabolism indicate therapeutic potential for leucine–PDE5 inhibitor combinations

Improved laccase production by Trametes versicolor using Copper-Glycyl-L-Histidyl-L-Lysine as a novel and high-efficient inducer

A highly efficient strategy using Copper-Glycyl-L-Histidyl-L-Lysine (GHK-Cu) as a novel inducer was developed to enhance laccase production by Trametes versicolor. After medium optimization, laccase activity increased by 12.77-fold compared to that without GHK-Cu. The laccase production of 1113.8 U L−1 was obtained by scaling-up culture in 5-L stirring tank. The laccase production induced by CuSO4 was poorer than that of GHK-Cu at the same mole concentration. GHK-Cu could increase the permeability of cell membrane with less damage, and it facilitated the adsorption, accumulation, and utilization of copper by fungal cells, which was beneficial for laccase synthesis. GHK-Cu induced better expression of laccase related genes than that of CuSO4, resulting in higher laccase production. This study provided a useful method for induced production of laccase by applying GHK chelated metal ion as a non-toxic inducer, which reduced the safety risk of laccase broth and provided the potential application of crude laccase in food industry. In addition, GHK can be used as the carrier of different metal ions to enhance the production of other metalloenzymes

Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field

The wave equation with internal control in non-cylindrical domains

Abstract In this paper, we shall be concerned with interior controllability for a one-dimensional wave equation in a domain with moving boundary. When the speed of the moving endpoint is less than a certain constant which is less than the characteristic speed, we obtain exact controllability for this equation

The wave equation with locally distributed control in non-cylindrical domain

Abstract This paper is concerned with exact internal controllability for a one-dimensional wave equation in a non-cylindrical domain. This equation characterizes the motion of a string with a fixed endpoint and the other moving one. When the speed of the moving endpoint is less than wave speed, exact internal controllability of this equation is established